MCQ Detailed View

Refraction is the bending of a wave when it passes through regions where its speed changes. Although students often learn about refraction in the context of light waves, the same principle also applies to sound waves. Refraction of sound waves can occur in both air and water, because in both media the speed of sound can vary depending on conditions such as temperature, density, and pressure.

In air, sound travels faster in warmer regions than in cooler ones. If a layer of air near the ground is cooler while the air above is warmer, sound waves bend upward. On the other hand, if the ground is heated and the air above is cooler, sound bends downward, making distant sounds easier to hear. This phenomenon explains why sound sometimes travels farther at night when the air near the ground is cooler and denser compared to the air above.

In water, sound refraction is influenced by temperature, salinity, and depth (pressure). For example, in the ocean, sound speed generally increases with higher temperature and pressure. This creates a layered effect where sound bends toward regions of slower speed. This principle is used in sonar technology and in studying the ocean’s “SOFAR channel,” a layer that allows sound to travel very long distances with minimal loss of energy.

The refraction of sound in both air and water demonstrates that sound waves behave like other types of waves, responding to changes in the medium through which they pass. Understanding this property is an important part of physics and helps explain natural phenomena as well as practical applications in acoustics, meteorology, and marine science.